Development of Combinatorial Thinking Ability Questions for Students

This study aims to develop a question instrument that can measure combinatorial thinking skills in students. The method used is the 4-D development model, which consists of Define, Design, Develop, and Disseminate stages. The questions developed were tested on 20 students of Mathematics Education at PGRI Argopuro University Jember. The validation results by two validators showed that the question had a validity level with an average value of 3.71, which was included in the valid category. Reliability testing using Alpha Cronbach yielded a value of 0.931, indicating high reliability. Field test data showed that 65% of students were in the medium combinatorial thinking ability category and 35% in the high category. The highest indicator of combinatorial thinking ability is identifying several problems (96%), while the lowest is considering several combinations of other issues (34.16%). The developed instrument is expected to help analyze students’ combinatorial thinking ability and can be used in similar research or teaching in the future.